BSNL now a days is providing a adsl router made by SemIndia Systems and the model names are similar to DNA-A201 or DNA-A211-1. In this article we are going to hack into this router to learn more about it. You might not know that this small and innocent looking modem is actually a “Linux CPU”…. Read More »
UDP sockets UDP stands for User Datagram Protocol and is an alternative protocol to TCP the most common protocol used for data transfer over the internet. UDP is different from TCP in a number of ways. Most importantly UDP is a connectionless protocol. TCP vs UDP In the TCP protocol first a connection is established… Read More »
Nameservers are special servers running a DNS service to provide the ip address of a particular domain name. Different domains have different nameservers. Usually the nameservers are hosted and managed by the hosting server provider. If you are hosting your website on Bluehost for instance, the nameservers would be those of bluehost. Whereas if you… Read More »
Dropdown terminal is a very useful utility that shows a command line terminal in a dropdown popup on the screen just by pressing a button like F12. These provide easy access to the command line and enhance productivity on Linux Desktop. There are multiple packages available for Ubuntu and similar distros, that provide a dropdown… Read More »
UDP sockets This article describes how to write a simple echo server and client using udp sockets in C on Linux/Unix platform. UDP sockets or Datagram sockets are different from the TCP sockets in a number of ways. The most important difference is that UDP sockets are not connection oriented. More technically speaking, a UDP… Read More »
Port Forwarding Port forwarding is a configuration in the router of a LAN such that any connections to a specific port number on the public/wan ip of the router may be forwarded to a specific machine/ip inside the LAN. Most routers have configuration options to enable port forwarding. Testing Port Forwarding After setting up port… Read More »
Netcat is a commandline utility like telnet but with much more features. Learn to use netcat with these simple commands examples.
Arp-scan Arp-scan is a commandline utility for linux that can be used to scan the network of a certain interface for alive hosts. It shows the ip address and mac addresses of all the hosts/nodes found. Project website Install on ubuntu $ sudo apt-get install arp-scan The documentation can be found at Usage Quick example… Read More »
Nmap Nmap (Network Mapper) is the most popular port scanner and network discovery tool used. It can be used to scan a network for live hosts and scan hosts for open ports. Besides port scanning there are many more things that Nmap can do like OS identification, running user scripts etc. It is widely used… Read More »
Tsocks There are many network applications that do not have the option to specify a proxy or do not support the use of proxies. In such cases tsocks is a useful tool to wrap all network communication done by a program via a socks proxy. Project website Install on ubuntu $ sudo apt-get install tsocks… Read More »
The most common compressed archive file format in Linux is the tar.gz format. Tar file is an archive file format. Tar.gz is a compressed tar file. Create tar.gz archives The tar command can be used to create tar.gz archives. tar czf new-tar-file-name.tar.gz file-or-folder-to-archive Here is the command explanation: c – create new archive. z -… Read More »
TOR is an anonymity solution that can be used as a proxy over the internet. Project website Install on Ubuntu $ sudo apt-get install tor vidalia During the installation a configuration screen will come up, asking to select those users who would be using tor. Select the appropriate users on that page and continue. After… Read More »
Nikto Nikto is a vulnerability scanner that scans webservers for thousands of vulnerabilities and other known issues. It is very easy to use and does everything itself, without much instructions. It is included by default in pen testing distros like Kali linux. On other oses/platforms you need to install it manually. Can be downloaded from… Read More »
SQLite Database Browser is a freeware, public domain, open source visual tool used to create, design and edit database files compatible with SQLite. It is meant to be used for users and developers that want to create databases, edit and search data using a familiar spreadsheet-like interface, without the need to learn complicated SQL commands…. Read More »
In a previous article we saw how to use sqlmap to exploit vulnerable urls of the form http://www.site.com/section.php?id=59 where the id parameter for example is vulnerable to sql injection. Now we shall try to do the same thing with forms, especially login forms. Forms often submit data via post, so the sytanx for launching the… Read More »
Sqlmap is the most popular tool for carrying out automated sql injections against vulnerable systems. In this tutorial we are going to learn to use it.
Socket function – recv() If you are writing a socket program in python that communicates with some remote machine or server to receive data, then you shall be using the recv() function to receive data on a socket. The recv() can receive only a specified number of bytes into a string buffer. If the incoming… Read More »
The DomDocument class in php can be used to parse html/xml content and build objects that can be queried using standard functions to extract values. The following functions are quite useful: getElementsByTagName – Get all elements under a node that match a tagname getNamedItem – Get element with a particular “name=” attribute. Useful to find… Read More »
Scraper scripts often need to extract all links on a given page. This can be done in a number of ways like regex, domdocument etc. Here is simple code snippet to do this using domdocument. /* Function to get all links on a certain url using the DomDocument */ function get_links($link) { //return array $ret… Read More »
Often numbers are to be written with a proper suffix, like 1st, 2nd, 3rd, 15th, 21st and so on. So here is a quick function to do the same for a number. Technique 1 /* This function will add st, nd, rd, th to the end of numbers */ function ordinal($i) { $l = substr($i,-1);… Read More »